In the vast majority of applications, no adhesive is required; the tiles can be dry laid and will take forklift or vehicle traffic without a problem.
The only instances in which the tiles may require gluing is when there is a fork truck with a very high point loading (for example a three-wheel electric reach truck with the batteries located over the back wheel) that operates in a confined space with very tight turning circles. Or when part of the floor is likely to be exposed to much higher temperatures than the rest of the floor (e.g. in front of a furnace or oven or adjacent to a south-facing loading bay door).